LOCATION JACOBY IDTentative Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, frigid Calcic Haploxerolls
TYPICAL PEDON: Jacoby fine sandy loam on a southwest facing, linear 2 percent slope, under shrubs at an elevation of 1706 meters. When described on April 26, 2004, the soil was moist throughout. (Colors are for dry soil unless otherwise noted.)
A1--0 to 5 cm; brown (10YR 4/3) fine sandy loam, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; soft, very friable, nonsticky and nonplastic; common very fine and fine roots; few very fine and fine vesicular pores; 5 percent gravel; slightly acid (pH 6.4); clear smooth boundary.
A2--5 to 15 cm: brown (10Yr 4/3) fine sandy loam, dark brown(10YR 3/3) moist; weak fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine and fine and few medium roots; few very fine and fine vesicular pores; 5 percent gravel; neutral (pH 7.3); abrupt smooth boundary. (The combined thickness of the A horizons ranges from 5 to 20 cm)
ABk--15 to 28 cm; brown (10YR 4/3) fine sandy loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; many very fine and fine roots; common very fine and fine vesicular pores; finely disseminated calcium carbonate in the matrix, few fine weakly cemented carbonate nodules in the matrix; slightly effervescent (11 percent carbonate); 10 percent gravel; slightly alkaline (pH 7.6); abrupt smooth boundary. (13 to 18 cm thick)
Bk1--28 to 41 cm; brown (10YR 5/3) loam, brown (10YR 4/3) moist; moderate medium subangular blocky structure parting to strong fine subangular blocky; soft, very friable, slightly sticky and slightly plastic; many very fine and fine roots; few very fine and fine vesicular pores; finely disseminated calcium carbonate in the matrix, common fine, medium and coarse indurated carbonate nodules in the matrix; violently effervescent (28 percent calcium carbonate); 12 percent gravel including nodules; slightly alkaline (pH 7.7); clear wavy boundary.
Bk2--41 to 102 cm; light gray (10YR 7/2) gravelly loam, pale brown (10YR 6/3) moist; moderate medium subangular blocky structure; slightly hard, firm, slightly sticky and slightly plastic; few very fine and fine roots; few very fine and fine vesicular pores; finely disseminated calcium carbonate in the soil matrix and less than 1 mm thick calcium carbonate coats on faces of peds and coating rock fragments, common fine, medium and coarse indurated carbonate nodules in the matrix; violently effervescent (30 percent calcium carbonate); 18 percent gravel including nodules; slightly alkaline (pH 7.7); clear wavy boundary. (The combined thickness of the Bk horizons 47 to 99 cm)
Bkq--102 to 150 cm; light gray (10YR 7/2) extremely gravelly sandy loam, pale brown (10YR 6/3) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; few very fine vesicular pores; 1 to 3 mm thick carbonate and silica coatings on rock fragments, many fine, medium and coarse irregular indurated calcium carbonate nodules in the matrix; violently effervescent (27 percent carbonate); 50 percent gravel including nodules, 20 percent cobbles; strongly alkaline (pH 8.8); gradual wavy boundary. (35 to 48 cm thick)
2R--150 cm; vesicular basalt
TYPE LOCATION: Clark County, Idaho; about 18 kilometers east of Dubois, Idaho; about 126 meters north and 116 meters west of the south east corner, sec. 24, T. 10 N., R. 37 E.; USGS Dubois NE, Idaho topographic quadrangle; latitude 44 degrees, 11 minutes, 5.2 seconds N. and longitude 112 degrees, 2 minutes, 5.2 seconds W.; NAD 83.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature: 6 to 7.5 degrees C. (Frigid soil temperature regime)
Mean summer soil temperature: 17 to 21 degrees C.
Thickness of mollic epipedon: 28 to 36 cm
Depth to calcic horizon: 5 to 20 cm
Particle size control section clay content: Total 15 to 20 percent; carbonate 2 to 10 percent; noncarbonate 8 to 12 percent
Depth to bedrock: 100 to 152 cm
A horizons
Value: 4 or 5 dry
Chroma: 2 or 3 moist or dry
Rock fragment content: 0 to 5 percent gravel
Clay: Total 10 to 25 percent
Reaction: Slightly acid to neutral
ABk horizon
Value: 4 through 7 dry, 3 or 4 moist
Chroma: 2 or 3 moist
Rock fragment content: 0 to 10 percent gravel
Textures: VFSL or L
Calcium carbonate equivalent: 5 to 15 percent
Clay content: total 15 or 20 percent; carbonate 2 to 5 percent; noncarbonate 10 to 18 percent
Reaction: Slightly to moderately alkaline
Bk horizons
Value: 5 through 8 dry , 4 through 7 moist
Chroma: 2 or 3 moist or dry
Textures: GR-L or L
Rock fragment content: 0 to 20 percent gravel
Clay content: Total 15 to 20 percent; carbonate 5 to 10 percent; noncarbonate 5 to 15 percent
Reaction: Slightly to strongly alkaline
Calcium carbonate equivalent: 15 to 50 percent with a weighted average between 25 and 40 percent.
Nodules: 5 to 45 percent weakly to moderately cemented cicada nodules
Bkq horizons
Hue: 2.5Y or 10YR
Rock fragment content: 5 to 70 percent total, 0 to 50 percent gravel including indurated nodules, 5 to 20 percent cobbles
Textures: SL, GR-SL, GRV-SL, GRX-SL
Clay content: Total 12 to 18 percent; carbonate 5 to 10 percent; noncarbonate 5 to 10 percent
Calcium carbonate equivalent: 15 to 50 percent with a weighted average of 25 to 40 percent
Reaction: Strongly to very strongly alkaline
Other features: Some pedons may have a thin discontinuous weakly cemented horizon above the bedrock. Indurated calcium carbonate nodules range from 0 to 25 percent. Rock fragments may be coated with a carbonate and silica 1 to 5 mm thick.
COMPETING SERIES: These are the Arbone, Blacknoll, Kackley and Kearl series. Arbone soils are very deep. Blacknoll and Kackley soils are moderately deep. Kearl formed in residuum and colluvium from sandstone and has hue of 7.5YR through 2.5YR.
GEOGRAPHIC SETTING:
Landscape: Lava fields
Landform: lava flow
Elevation: 1585 to 1768 meters
Slope: 1 to 8 percent
Parent Material: Loess and eolian sand over residuum from basalt
Mean annual precipitation: 305 to 406 mm
Mean annual air temperature: 5 to 7 degrees C.
Frost-free period: 70 to 95 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Blacknoll, Eaglecone (T), Jipper, Nayrib and Hotspot. Blacknoll soils are moderately deep. Eaglecone soils have greater than 35 percent coarse fragments in the particle-size control section. Jipper soils have a mollic epipedon over 50 centimeters thick. Nayrib soils are very shallow to bedrock. Hotspot soils are shallow to bedrock.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class: Well drained
Runoff: Very low and low
Saturated Hydraulic Conductivity: High
USE AND VEGETATION:
Major uses: Rangeland and wildlife habitat
Range Site: R011BY011ID
Dominant native vegetation; threetip sagebrush, Wyoming big sagebrush, twisted leaf rabbitbrush, antelope bitterbrush, bluebunch wheatgrass, Nevada bluegrass, Sandberg bluegrass, needleandthread, carex, prairie junegrass, hoods phlox, bushy birdsbeak, horsebrush, prickly pear, buckwheat, lupine, biscuitroot, milkvetch, wild onion, death camas, tapertip hawksbeard, and arrowleaf balsamroot.
DISTRIBUTION AND EXTENT: Eastern Idaho; MLRA 11, 12, and 13 The series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Portland, Oregon
SERIES PROPOSED: Clark County, Idaho, 1959.
REMARKS: Diagnostic horizons and features in this pedon include:
Mollic epipedon: the zone from 0 to 28 cm (A1, A2 and ABk horizons)
Calcic horizon: the zone from 15 to 150 cm (ABk, Bk1, Bk2 and Bkq horizons)
Particle size control section: the zone from 25 to 100 cm
Lithic contact: 150 cm (2R horizon)
Soil moisture regime: Xeric
Soil Temperature regime: Frigid
The 2008 OSD revision moves the type location within the survey area.